One of the hallmark techniques of street shooting has always been using hyper focal distance . On a Leica M you place the infinity mark at the F stop and you can see that everything from your navel to the moon should be in focus . Close inspection would show that this is only true in the most liberal definitions of “in focus “ . With larger sensors (and it appears smaller pixels ) DOF seems to have disappeared .
A recent blog post on Diglloyd (on the free blog) presents a theory ? that DOf should be calculated by using a circle of confusion that mirrors the pixel size .
You could easily see this with MF at wide apertures but I had always considered this a difference in focal lengths . Using an M9 and a S2 the pixel pitch is close and so a 70mm lens has the same DOF on both cameras (but different equivalent FOV)..so all I was seeing was the fact that a 70 on the S2 was a 50 on the M9.
Street shooters are taught to get close and use wide angle lens .....the more you shoot the closer you can get ......but as pixel pitch gets below 5 ... you just don t have adequate DOF to cover subject movement . But the same concept applies to many different subjects .
Add in that optimum aperture is often between f4 and f5.6 and I ve found my limiting factor with the D800E .....